• 제목/요약/키워드: gamma mixed model

검색결과 62건 처리시간 0.031초

Hot Wall Epitaxy(HWE)법에 의해 성장된 $CdIn_2S_4$ 단결정 박막의 가전자대 갈라짐에 대한 광전류 연구 (Photocurrent Study on the Splitting of the Valence Band and Growth of $CdIn_2S_4$/GaAs Single Crystal Thin Film by Hot Wall Epitaxy)

  • 백승남;홍광준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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    • pp.79-80
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    • 2006
  • A stoichiometric mixture of evaporating materials for $CdIn_2S_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $CdIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-Insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The temperature dependence of the energy band gap of the $CdIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation. $E_g(T)=2.7116 eV-(7.74{\times}10^{-4} eV)T^2/(T+434)$. The crystal field and the spin-orbit splitting energies for the valence band of the $CdIn_2S_4$ have been estimated to be 0.1291 eV and 0.0248 eV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $AgInS_2$/GaAs epilayer. The three photocurrent peaks observed at 10K are ascribed to the $A_1-$, $B_1-$, and C1-exciton peaks for n = 1.

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$CuAlSe_2$ 단결정 박막의 성장과 광전류 특성 (Growth and Photocurrent Properties for $CuAlSe_2$ Single Crystal Thin film)

  • 홍광준;백승남
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.226-229
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    • 2004
  • A stoichiometric mixture of evaporating materials for $CuAlSe_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $CuAlSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $680^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CuAlSe_2$ single crystal thin films measured with Hall effect by van der Pauw method are $9.24{\times}10^{16}\;cm^{-3}$ and $295\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CuAlSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)\;=\;2.8382\;eV\;-\;(8.68{\times}10^{-4}\;eV/K)T^2/(T+155K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $CuAlSe_2$ have been estimated to be 0.2026 eV and 0.2165 eV at 10K, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $CuAlSe_2$. The three photocurrent peaks observed at 10K are ascribed to the $A_1-$, $B_1-$, and $C_1$-exciton peaks for n = 1.

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오미자 Schizandrin C 유도체 DDB 복합물 DWP-04가 Acetaminophen 해독계에 미치는 영향 (Evaluation of a Schzandrin C Derivative DDB-mixed Preparation(DWP-04) on Acetaminophen Detoxification Enzyme System in the Animal Model)

  • 박희준;이명선;지상철;이경태;신영호;최종원
    • 생약학회지
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    • 제36권2호통권141호
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    • pp.81-87
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    • 2005
  • The effects of the DWP-04 [DDB:selenium yeast:glutathione (31.1 : 6.8 : 62.1 (w/w%)] on acetaminophen detoxification enzyme system were studied in rats. Treatment with DWP-04 was prevented againt acetaminophen-induiced hepatotoxicity in rat as evidenced by the decreased formation of lipid peroxide. Effect of DWP-04 on the activities of free radical-generating enzymes, free radical scavenging enzymes and glutathione-related enzymes as well as detoxification mechanism of DWP-04 against acetaminophen-treated was investigated in rat. Activities of cytochrome p450, cytochrome b5, aminopyrine demethylase and aniline hydroxylase as free radical-generating enzymes activities were decreased by the treatment with DWP-04 against acetaminophen treated. Although acetaminophen-induced hepatotoxicity results in the significantly decrease in the level of hepatic glutathione and activities of glutathine S-transferase, quinone reductase, glutathione reductase and ${\gamma}-glutamyl-$cysteine synthetase, these decreasing effects were markedly lowered in the DWP-04-treated rat. Therefore, it was concluded that the mechanism for the observed preventive effect of DWP-04 against the acetaminophen-induced hepatotoxicity was associated with the decreased activities in the free radical-generating enzyme system.

Hot Walll Epitaxy (HWE)법에 의한 $CuInSe_2$ 단결정 박막 성장과 가전자대 갈라짐에 대한 광전류 연구 (Growth and Photocurrent Study on the Splitting of the Valence Band for $CuInSe_2$ Single Crystal Thin Film by Hot Wall Epitaxy)

  • 윤석진;홍광준
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.234-238
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    • 2004
  • A stoichiometric mixture of evaporating materials for $CuInSe_2$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $CuInSe_2$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the hot wall epitaxy (HWE) system. The source and substrate temperatures were $620^{\circ}C$ and $410^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by the photoluminescence and double crystal X-ray diffraction (DCXD). The carrier density and mobility of $CuInSe_2$ single crystal thin films measured with Hall effect by van der Pauw method are $9.62{\times}10^{l6}\;cm^{-3}$ and $296\;cm^2/V{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $CuInSe_2$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)\;=\;1.1851\;eV\;-\;(8.99{\times}10^{-4}\;eV/K)T^2/(T+153K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $CuInSe_2$ have been estimated to be 0.0087 eV and 0.2329 eV at 10K, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}_{so}$ definitely exists in the $\Gamma_6$ states of the valence band of the $CuInSe_2$. The three photocurrent peaks observed at 10K are ascribed to the $A_1-$, $B_1-$, and $C_1$-exciton peaks for n = 1.

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Hot Wall Epitaxy(HWE)법에 의한 BaIn2S4 단결정 박막 성장과 광전도 특성 (Growth and optical conductivity properties for BaIn2S4 single crystal thin film by hot wall epitaxy)

  • 정경아;홍광준
    • 한국결정성장학회지
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    • 제25권5호
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    • pp.173-181
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    • 2015
  • A stoichiometric mixture of evaporating materials for $BaIn_2S_4$ single crystal thin films was prepared from horizontal electric furnace. To obtain the single crystal thin films, $BaIn_2S_4$ mixed crystal was deposited on thoroughly etched semi-insulating GaAs(100) substrate by the Hot Wall Epitaxy (HWE) system. The source and substrate temperatures were $620^{\circ}C$ and $420^{\circ}C$, respectively. The crystalline structure of the single crystal thin films was investigated by double crystal X-ray diffraction (DCXD). The carrier density and mobility of $BaIn_2S_4$ single crystal thin films measured from Hall effect by van der Pauw method are $6.13{\times}10^{17}cm^{-3}$ and $222cm^2/v{\cdot}s$ at 293 K, respectively. The temperature dependence of the energy band gap of the $BaIn_2S_4$ obtained from the absorption spectra was well described by the Varshni's relation, $E_g(T)=3.0581eV-(3.9511{\times}10^{-3}eV/K)T^2/(T+536K)$. The crystal field and the spin-orbit splitting energies for the valence band of the $BaIn_2S_4$ have been estimated to be 182.7 meV and 42.6 meV, respectively, by means of the photocurrent spectra and the Hopfield quasicubic model. These results indicate that the splitting of the ${\Delta}so$ definitely exists in the ${\Gamma}_5$ states of the valence band of the $BaIn_2S_4/GaAs$ epilayer. The three photocurrent peaks observed at 10 K are ascribed to the $A_1$-, $B_1$-exciton for n = 1 and $C_{24}$-exciton peaks for n = 24.

Variance Components and Genetic Parameters for Milk Production and Lactation Pattern in an Ethiopian Multibreed Dairy Cattle Population

  • Gebreyohannes, Gebregziabher;Koonawootrittriron, Skorn;Elzo, Mauricio A.;Suwanasopee, Thanathip
    • Asian-Australasian Journal of Animal Sciences
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    • 제26권9호
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    • pp.1237-1246
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    • 2013
  • The objective of this study was to estimate variance components and genetic parameters for lactation milk yield (LY), lactation length (LL), average milk yield per day (YD), initial milk yield (IY), peak milk yield (PY), days to peak (DP) and parameters (ln(a) and c) of the modified incomplete gamma function (MIG) in an Ethiopian multibreed dairy cattle population. The dataset was composed of 5,507 lactation records collected from 1,639 cows in three locations (Bako, Debre Zeit and Holetta) in Ethiopia from 1977 to 2010. Parameters for MIG were obtained from regression analysis of monthly test-day milk data on days in milk. The cows were purebred (Bos indicus) Boran (B) and Horro (H) and their crosses with different fractions of Friesian (F), Jersey (J) and Simmental (S). There were 23 breed groups (B, H, and their crossbreds with F, J, and S) in the population. Fixed and mixed models were used to analyse the data. The fixed model considered herd-year-season, parity and breed group as fixed effects, and residual as random. The single and two-traits mixed animal repeatability models, considered the fixed effects of herd-year-season and parity subclasses, breed as a function of cow H, F, J, and S breed fractions and general heterosis as a function of heterozygosity, and the random additive animal, permanent environment, and residual effects. For the analysis of LY, LL was added as a fixed covariate to all models. Variance components and genetic parameters were estimated using average information restricted maximum likelihood procedures. The results indicated that all traits were affected (p<0.001) by the considered fixed effects. High grade $B{\times}F$ cows (3/16B 13/16F) had the highest least squares means (LSM) for LY ($2,490{\pm}178.9kg$), IY ($10.5{\pm}0.8kg$), PY ($12.7{\pm}0.9kg$), YD ($7.6{\pm}0.55kg$) and LL ($361.4{\pm}31.2d$), while B cows had the lowest LSM values for these traits. The LSM of LY, IY, YD, and PY tended to increase from the first to the fifth parity. Single-trait analyses yielded low heritability ($0.03{\pm}0.03$ and $0.08{\pm}0.02$) and repeatability ($0.14{\pm}0.01$ to $0.24{\pm}0.02$) estimates for LL, DP and parameter c. Medium heritability ($0.21{\pm}0.03$ to $0.33{\pm}0.04$) and repeatability ($0.27{\pm}0.02$ to $0.53{\pm}0.01$) estimates were obtained for LY, IY, PY, YD and ln(a). Genetic correlations between LY, IY, PY, YD, ln(a), and LL ranged from 0.59 to 0.99. Spearman's rank correlations between sire estimated breeding values for LY, LL, IY, PY, YD, ln(a) and c were positive (0.67 to 0.99, p<0.001). These results suggested that selection for IY, PY, YD, or LY would genetically improve lactation milk yield in this Ethiopian dairy cattle population.

Hot Wall Epitaxy(HWE)범에 의한 $CuInSe_2$ 단결정 박막 성장과 가전자대 갈라짐에 대한 광전류 연구 (Growth and photocurrent study on the splitting of the valence band for $CuInSe_2$ single crystal thin film by hot wall epitaxy)

  • 홍명석;홍광준
    • 한국결정성장학회지
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    • 제14권6호
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    • pp.244-252
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    • 2004
  • $CuISe_2$ 단결정 박막은 수평 전기로에서 합성한 $CuInSe_2$ 다결정을 증발원으로하여, hot wall epitaxy(HWE) 방법으로 증발원과 기판(반절연성-GaAs(100))의 온도를 각각 $620^{\circ}C$, $410^{\circ}C$로 고정하여 단결정 박막을 성장하였다. 이때 단결정 박막의 결정성은 광발광 스펙트럼과 이중결정 선 요동곡선(DCRC) 으로 부터 구하였다. Hall 효과는 van der Pauw 방법에 의해 측정되었으며, 293K에서 운반자 농도와 이동도는 각각 $9.62\times10^{16}/\textrm{cm}^3$, 296 $\textrm{cm}^2$/Vㆍs 였다. $CuAlSe_2$/Si(Semi-Insulated) GaAs(100) 단결정 박막의 광흡수와 광전류 spectra를 293k에서 10K까지 측정하였다. 광흡수 스펙트럼으로부터 band gap $E_g$(T)는 Varshni 공식에 따라 계산한 결과 1.1851 eV-($8.99\times10^{-4} eV/K)T^2$/(T+153k)였다. 광전류 스펙트럼으로 부터 Hamilton matrix(Hopfield quasicubic mode)법으로 계산한 결과 crystal field splitting Δcr값이 0.0087eV이며 spin-orbit Δso값은 0.2329 eV임을 확인하였다. 10K일 때 광전류 봉우리들은 n = 1일때 $A_1-, B_1$-와 $C_1$-exciton봉우리임을 알았다.

Herbal extract THI improves metabolic abnormality in mice fed a high-fat diet

  • Han, So-Ra;Oh, Ki-Sook;Yoon, Yoo-Sik;Park, Jeong-Su;Park, Yun-Sun;Han, Jeong-Hye;Jeong, Ae-Lee;Lee, Sun-Yi;Park, Mi-Young;Choi, Yeon-A;Lim, Jong-Seok;Yang, Young
    • Nutrition Research and Practice
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    • 제5권3호
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    • pp.198-204
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    • 2011
  • Target herbal ingredient (THI) is an extract made from two herbs, Scutellariae Radix and Platycodi Radix. It has been developed as a treatment for metabolic diseases such as hyperlipidemia, atherosclerosis, and hypertension. One component of these two herbs has been reported to have anti-inflammatory, anti-hyperlipidemic, and anti-obesity activities. However, there have been no reports about the effects of the mixed extract of these two herbs on metabolic diseases. In this study, we investigated the metabolic effects of THI using a diet-induced obesity (DIO) mouse model. High-fat diet (HFD) mice were orally administered daily with 250 mg/kg of THI. After 10 weeks of treatment, the THI-administered HFD mice showed reduction of body weights and epididymal white adipose tissue weights as well as improved glucose tolerance. In addition, the level of total cholesterol in the serum was markedly reduced. To elucidate the molecular mechanism of the metabolic effects of THI in vitro, 3T3-L1 cells were treated with THI, after which the mRNA levels of adipogenic transcription factors, including C/$EBP{\alpha}$ and $PPAR{\gamma}$, were measured. The results show that the expression of these two transcription factors was down regulated by THI in a dose-dependent manner. We also examined the combinatorial effects of THI and swimming exercise on metabolic status. THI administration simultaneously accompanied by swimming exercise had a synergistic effect on serum cholesterol levels. These findings suggest that THI could be developed as a supplement for improving metabolic status.

자침이 중풍환자의 뇌파 변화에 미치는 영향 (The Effects of Acupuncture on the Electroencephalogram of Patients with Stroke)

  • 윤가영;박지민;김동혁;선종인;강중원;남동우;이승덕;최도영;이재동
    • Journal of Acupuncture Research
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    • 제29권5호
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    • pp.1-16
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    • 2012
  • Objectives : The purpose of this study was to examine the effects of manual acupuncture at the $LI_4$, $ST_{36}$ and $LR_3$ on Electroencephalogram(EEG) of patients with stroke. Methods : 32 channel EEG measurement was carried out in 35 Stroke patients(23 males and 12 females). EEG was measured for 21 minutes(made up of 7 sessions, 1 session means 3 minutes time interval) including 15 minutes(5 sessions) of acupuncture time. Power spectrum analysis was used as a measure of complexity. Statistical analysis was performed using Linear mixed model and DUNNETT's multiple comparison. Results : The results were as follows; 1. EEG amplitude was reduced during acupuncture except electrodes PG1 and PG2. 2. There was a notable change during 6~9 minutes after needling in ${\delta}{\cdot}{\beta}{\cdot}{\gamma}$ wave, and during 6~9 minutes after needling in ${\Theta}{\cdot}{\alpha}$ wave. Overall, during 6~9 minutes after needling. 3. TP8 is a common significant electrode among five wave forms. Conclusions : These results suggest that TP8 could be typical electrodes and change of EEG compared to baseline happens most often during 6~9 minutes after manipulated acupuncture at the $LI_4$, $ST_{36}$ and $LR_3$ of patients with stroke.

Adipogenesis에서 히스톤 H3 lysine methylation (Histone H3 Lysine Methylation in Adipogenesis)

  • 장영훈
    • 생명과학회지
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    • 제30권8호
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    • pp.713-721
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    • 2020
  • Adipogenesis의 연구는 인간의 지방생물학의 기초적인 분자기전을 이해하고, 비만, 당뇨 및 대사성 증후군의 발병기전을 밝히는데 필요하다. Adipogenesis의 많은 연구가 adipocytes 특이적인 핵심 전사인자인 PPARγ와 C/EBPα를 중심으로 하는 유전자 발현조절 및 세포 내 신호전달에 초점이 맞추어 활발하게 연구가 진행되었다. 그러나, 에피지놈 변형효소나 히스톤 돌연변이에 의한 에피지놈 관점에서 adipogenesis 연구는 미흡한 실정이다. 포유동물에서 히스톤 methylation은 유전자 발현에 대한 주요 후성유전적(epigenome) 변형 중 하나이며, 특히 히스톤 H3 lysine methylation은 다양한 조직 및 기관 발생과정과 세포 분화에 매우 중요한 히스톤 변형이다. 세포 특이적 enhancer는 adipogenesis에서 active enhancer 표지자인 H3K27ac와 함께 H3K4me1로 변형된다. MLL4는 Pparg 및 Cebpa 유전자 ehancers에서 중요한 adipogenic H3K4 mono-methyltransferase이다. 따라서 MLL4는 adipogenesis에 중요한 에피지놈 변형효소라고 할 수 있다. 유전자 발현 억제를 유발하는 대표적인 히스톤 변형인 H3K27me3은 Polycomb repressive complex 2의 효소활성 subunit인 Ezh2에 의해 매개된다. Wnt 유전자에서 Ezh2에 의한 H3K27me3 히스톤 methylation 변형은 adipogenesis를 증가시키는데, 이는 WNT 신호 전달이 adipogenesis의 억제 조절자로 알려져 있기 때문이다. 본 논문은 유전자 발현을 근본적으로 조절하는 히스톤 H3 methylation에 의한 후성 유전학적인 조절이 어떻게 adipogenesis를 조절하는지에 대해 요약한다.